Moldy Corn Could Cause More Problems If Not Stored Properly

Corn farmers across Illinois, Indiana and Ohio are battling moldy corn, which causes challenges from a grain handling and storage standpoint. Richard Stroshine, a Purdue University researcher, offers tips and advice for farmers in the eastern Corn Belt dealing with diplodia, giberella and other corn ear rots.

"I had one elevator manager tell me he hasn't seen anything like this since 1974," Stroshine says. "Farmers are going to have to take extra precaution in storing and drying down their grain this year."

Questions about moldy corn and reports of damage are coming into the university from all across the state. Stroshine says he talked with one farmer who estimated 15% of the kernels in his harvested corn were damaged by mold.

Farmers who have moldy corn should remove as much of the fine material or broken pieces of corn as possible, dry the grain down to 14-14.5% moisture and realize it's not going to store as well as it has in previous years, Stroshine says.

If fines aren't removed from the corn crop, they will impede airflow and promote the growth of mold within the grain bin, he explains.

"Mold can more easily grow on broken kernels because this is the food source for the fungi and it is more readily available," he says. "They also impede airflow during aeration of stored corn. So, getting rid of the fine material is a good strategy for improving grain storage, especially this year."

Stroshine recommends using the combine's full capabilities to help get rid of the fine material and incorporating high-capacity screen cleaners into the grain-handling system.

From a grain drying and handling standpoint, Stroshine says, farmers need to recognize that corn harvested with high moisture content will have more kernel damage; thus making it more susceptible to mold damage during storage.

There is a certain shelf life or storage time for grain, and putting it into a bin after it's been kept at high moisture content – even for a few days – reduces its shelf life, Stroshine says.

For example, a farmer decides to harvest the field and get it out of the weather to stop mold growth as soon as possible, Stroshine says. The farmer has a lot of wet corn waiting for several days to be dried and during this time while the corn is still wet, it loses its shelf life on the other end. The grain will be more susceptible to molding if it's stressed later on. So there's really a tradeoff, he says.

Even though it may slow down harvest, Stroshine recommends drying corn to below 15% moisture as soon as possible to help prevent further mold issues.

He recognizes the challenges producers face. They need to get the crop out of the field as soon as possible to prevent further damage and loss, but they also need to realize that because of the situation harvest is going to take longer, he says.

"More effort, fuel or propane, more time and more patience are going to be needed to successfully harvest, dry and store this year's crop," Stroshine says.

Planning is the key. Stroshine says producers should ask themselves, "Can I get it dried without leaving it at a high moisture content for an appreciable amount of time? Can I store it well? Can I handle it properly?"

If not, he says, it will only create another problem if the grain is taken from the field and piled up on the farmstead without being properly dried.

"Farmers may want to mix their moldy corn with their good corn, but my recommendation would be to segregate the good corn from the bad," Stroshine says. "It should be handled separately. Then if need be, the producer can blend it later."

More information about grain handling and storage is available. Matt Roberts, a former graduate student in the department who specialized in this area, is available to help answer technical questions regarding drying and storing this year's crop. Robert's goal is to help Hoosier producers and the grain industry maintain the quality of their corn and soybean crops at the highest possible level. He can be reached at 765-494-1174 or mroberts@purdue.edu.